#! /usr/bin/python
# coding: utf-8

from Tkinter import *

root = Tk()

def cb1():
    print 'button1 clicked'
    
def cb2():
    print 'button2 clicked'
    
def cb3(event):
    print 'button3 clicked'
    
b1 = Button(root, text = 'Button1', command = cb1)
b2 = Button(root, text = 'Button2', command = cb2)
b3 = Button(root, text = 'Button3')
b3.bind('<Return>', cb3)
b1.pack()
b2.pack()
b3.pack()
b3.focus_set()

root.mainloop()
